Pat Tillman was a star defensive player for the Arizona Cardinals when he quit the NFL in May 2002 to join the Army Rangers; he died in April 2004 in Afghanistan. The military and media moved quickly to anoint him a hero felled by the Taliban, but within weeks news broke that he’d been killed by friendly fire. This uncompromising documentary by Amir Bar-Lev (Fighter, My Kid Could Paint That) delves into the cover-up, which reached to the top levels of the armed forces, and recounts the dogged investigation by Pat’s mother, Dannie, as she combed through 3,000 pages of redacted government documents with the help of blogger and special-ops veteran Stan Goff. Bar-Lev ponders myth in both senses of the word—as a web of lies, but also as a psychological construct that gives life purpose. An atheist and a critical thinker, Pat Tillman had no use for either.